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1
Viladkar, Shrinivas G. "Fenitized pre-carbonatite Deccan basalts in and around the carbonatite diatreme of Amba Dongar, Gujarat, Western India." Journal of Geointerface 4, no. 1 (2025): 83–94. https://doi.org/10.5281/zenodo.15574645.
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The late Cretaceous carbonatite-nephelinite diatreme at Amba Dongar area in western India intrude into the sedimentary Bagh beds overlain by Deccan basalt sequence. Being situated on the western periphery of the Deccan flood basalt, the thickness of basalt cover is thin. Basalt (pre-carbonatite) covers the large part of the ring complex in the outer periphery while in the central part of the ring structure thin basalt cover of the pre-doming topography has been preserved. Fragments of this basalt are caught up in the carbonatite breccia rimming central basalt. Large number of post-carbonatite basalt and dolerite dikes intrude in to central basalt, carbonatite breccia and sövite. Pre-carbonatite Deccan basalt shows widespread fenitization effects induced by the emanation from carbonatite magma which resulted into replacement of pyroxene by calcite in these basalts. As a result, the basalt has acquired a composition of ‘plagioclase-calcite’ rocks. Chemically the fenitized basalts show increase in Si, K, Fe, Fe and CO2, Ba, Sr, Rb, and REE and decrease in Mg and Al. Na decreases in some fenitized basalts wherein plagioclase has been replaced by calcite. With help of major, trace and REE geochemistry the changes brought about in the pre-carbonatite basalt are presented and discussed.
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STRIEDER, ADELIR JOSÉ, and ROBERTO HEEMANN. "Structural Constraints on Paraná Basalt Volcanism and their Implications on Agate Geode Mineralization (Salto do Jacuí, RS, Brazil)." Pesquisas em Geociências 33, no. 1 (2006): 37. http://dx.doi.org/10.22456/1807-9806.19525.
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The Paraná-Etendeka Continental Flood Basalt province hosts world-class agate and amethyst geode deposits in Rio Grande do Sul (Brazil; Serra Geral Fm.). Salto do Jacuí Mining District (Rio Grande do Sul, Brasil) has different types of agate geode hosted in vesicular basalt. A series of structural features has recently been investigated in the Salto do Jacuí Mining District, and indicates at least two volcanic episodes: i) normal tholeiitic basalt and dacite eruption, and ii) vesicular basalt and dacite intrusions as sills and dikes. These structural features include: basalt and aeolian sandstone xenoliths in vesicular basalts, vesicular basalt apophyses in massive basalts, sandstone and basalt breccias, sandstone dikes cutting across vesicular lavas and connected to mixed sandstone-agate geodes, sandstone assimilation by vesicular lava, and mixed sandstone and agate geodes. These features show that agate geodes were formed by melting of Botucatu sandstone xenoliths. High density contrast between vesicular basalt and Botucatu sandstone melts makes them immiscible during flow. Botucatu sandstone xenoliths melting is favored by degasing of intrusive volatile-rich basalts. The high-silica globs crystallize dynamically in a closed-system environment, giving rise to agate banding and fibrosity.
3
Moyen, Jean-François. "Granites and crustal heat budget." Geological Society, London, Special Publications 491, no. 1 (2019): 77–100. http://dx.doi.org/10.1144/sp491-2018-148.
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AbstractThe origin of large I-type batholiths remains a disputed topic. One model states that I-type granites form by partial melting of older crustal lithologies (amphibolites or intermediate igneous rocks). In another view, granites are trapped rhyolitic liquids occurring at the end of fractionation trends defining a basalt–andesite–dacite–rhyolite series. This paper explores the thermal implications of both scenarios, using a heat balance model that abstracts the heat production and consumption during crustal melting. Heat is consumed by melting and by losses through the surface (conductive or advective, as a result of eruption). It is supplied as a basal conductive heat flux, as internal heat production or as advective heat carried by an influx of hot basalt into the crust. Using this abstract approach, it is possible to explore the role different parameters play in the balance of granites formed by differentiation of basalts or by crustal melting. Two end-member situations appear equally favourable to generating large volumes of granites: (1) short-lived environments dominated by high basaltic flux, where granites result mostly from basalt differentiation; and (2) long-lived systems with no or minimal basalt flux, with granites resulting chiefly from crustal melting.
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Karyakin, Yu V., G. N. Aleksandrova, and А. М. Никишин. "Early Jurassic Flood Basalt Volcanism on the Franz Josef Land Archipelago: Geological and Palynostratigraphical Data." Стратиграфия 31, no. 1 (2023): 27–51. http://dx.doi.org/10.31857/s0869592x23010039.
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Biostratigraphic evidence of the presence of Early Jurassic flood basalts on the Franz Josef Land archipelago is presented. The flood basalts form layered section with two units, which is not discovered for Early Cretaceous basalts. The lower unit is composed by large-columnar basalts (colonnade), and the upper unit by small-columnar (entablature) chaotic-fan basalts. On the Hooker Island, the basalt flow is exposed on the Sedov Plateau, on the Lunacharsky Rock Cape and, possibly, on Al’banov Cape. On the southern slope of the Sedov Plateau, the basalt flow overlaps sands and sandstones, which contain palynoassemblage of the lower Toarcian. In the Lunacharsky Rock Cape outcrop, the underlying basalt sands are of the Pliensbachian to Early Toarcian chronostratigraphic interval. Apart from the Hooker Island, we observed basalts with the “colonnade/entablature” on three other islands: Scott Keltie, May and Leigh-Smith. The most complete section was found in the western part of the Leigh-Smith Island, where basalts are underlain and overlapped by sand units. The underlying sands in contact with basalts have a quenching zone. There is no quenching zone at the contact with the overlapping sands. A palynocomplex from the lower sand unit is early Toarcian in age. The palynocomplex found in the upper sand unit indicates its accumulation in the interval from the lower part of the late Toarcian to the early Aalenian. A palynological study of the underlying and overlying deposits of the basalt flow has shown that the flow is underlain by continental and coastal-marine sediments of the Pliensbachian to the upper part of the early Toarcian age interval. Basalt flow is overlain by the earliest late Toarcian–early Aalenian marine sediments. According to the modern chronostratigraphic scale, the age of the basalt flow can be estimated as approximately 180 million years, which is quite consistent with the earlier obtained 40Ar/39Ar data of 189.1 ± 11.4 million years. These data indicate that the basalt flow was formed during a narrow stratigraphic interval of the uppermost lower–earliest upper Toarcian.
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Fliedner, Moritz M., and Robert S. White. "Seismic structure of basalt flows from surface seismic data, borehole measurements, and synthetic seismogram modeling." GEOPHYSICS 66, no. 6 (2001): 1925–36. http://dx.doi.org/10.1190/1.1486760.
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We use the wide‐angle wavefield to constrain estimates of the seismic velocity and thickness of basalt flows overlying sediments. Wide angle means the seismic wavefield recorded at offsets beyond the emergence of the direct wave. This wide‐angle wavefield contains arrivals that are returned from within and below the basalt flows, including the diving wave through the basalts as the first arrival and P‐wave reflections from the base of the basalts and from subbasalt structures. The velocity structure of basalt flows can be determined to first order from traveltime information by ray tracing the basalt turning rays and the wide‐angle base‐basalt reflection. This can be refined by using the amplitude variation with offset (AVO) of the basalt diving wave. Synthetic seismogram models with varying flow thicknesses and velocity gradients demonstrate the sensitivity to the velocity structure of the basalt diving wave and of reflections from the base of the basalt layer and below. The diving‐wave amplitudes of the models containing velocity gradients show a local amplitude minimum followed by a maximum at a greater range if the basalt thickness exceeds one wavelength and beyond that an exponential amplitude decay. The offset at which the maximum occurs can be used to determine the basalt thickness. The velocity gradient within the basalt can be determined from the slope of the exponential amplitude decay. The amplitudes of subbasalt reflections can be used to determine seismic velocities of the overburden and the impedance contrast at the reflector. Combining wide‐angle traveltimes and amplitudes of the basalt diving wave and subbasalt reflections enables us to obtain a more detailed velocity profile than is possible with the NMO velocities of small‐offset reflections. This paper concentrates on the subbasalt problem, but the results are more generally applicable to situations where high‐velocity bodies overlie a low‐velocity target, such as subsalt structures.
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Maresh, Jennifer, Robert S. White, Richard W. Hobbs, and John R. Smallwood. "Seismic attenuation of Atlantic margin basalts: Observations and modeling." GEOPHYSICS 71, no. 6 (2006): B211—B221. http://dx.doi.org/10.1190/1.2335875.
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Paleogene basalts are present over much of the northeastern Atlantic European margin. In regions containing significant thicknesses of layered basalt flows, conducting seismic imaging within and beneath the volcanic section has proven difficult, largely because the basalts severely attenuate and scatter seismic energy. We use data from a vertical seismic profile (VSP) from well 164/07-1 that penetrated [Formula: see text] of basalt in the northern Rockall Trough west of Britain to measure the seismic attenuation caused by the in-situ basalts. The effective quality factor [Formula: see text] of the basalt layer is found from the VSP to be 15–35, which is considerably lower (more attenuative) than the intrinsic attenuation measured on basalt samples in the laboratory. We then run synthetic seismogram models to investigate the likely cause of the attenuation. Full waveform 1D modeling of stacked sequences of lava flows based on rock properties from the same well indicates that much of the seismic attenuation observed from the VSP can be accounted for by the scattering effects of multiple thin layers with high impedance contrasts. Phase-screen seismic modeling of the rugose basalt surface at the top-of-basalt sediment interface, with the magnitude and wavelength of the relief constrained by a 3D seismic survey around the well, suggests that surface scattering from this interface plays a much smaller role than internal scattering in attenuating the seismic signal as it passes through the basalt sequence.
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Greenough, John D., and V. S. Papezik. "The petrology of North Mountain basalts from the wildcat oil well Mobil Gulf Chinampas N-37, Bay of Fundy, Canada." Canadian Journal of Earth Sciences 24, no. 6 (1987): 1255–60. http://dx.doi.org/10.1139/e87-119.
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Basalts totalling 236 m in thickness were intersected in the wildcat oil well Mobil Gulf Chinampas N-37 in the Bay of Fundy. A 5.5 m section of conventional core retrieved from the middle of the basalt section sampled two fine-grained, phenocryst-poor, amygdaloidal basalt flows. The basalts, though somewhat altered, show concentrations of ferromagnesian elements (e.g., Fe, Mg, Cr, Ni) and immobile elements (e.g., Zr, Nb, Ta, Hf) as well as chondrite-normalized REE patterns typical of high-Ti quartz-normative tholeiites and are identical to more evolved samples of the North Mountain basalts at Digby. These petrographic and geochemical characteristics allow correlation with middle unit flows of the North Mountain basalts. The lower unit of North Mountain basalt may be as thick in the well as in the Digby area (~200 m), but the upper unit is either missing or very thin (< 68 m). A 25 m thick sedimentary section just above the conventional core but within the basalt sequence has not been reported on land and hints at the existence of a basalt unit not present on North Mountain. The conclusion that North Mountain basalts occur in the Chinampas well suggests that the flows underlie most of the Bay of Fundy, originally covered 9400 km2, and had a total volume of 2350 km3.
8
K, Rashidova R., Kurbanov Abdirakhim Ahmedovich, Aliyev T, Jiyanov A. B, Turdieva O. J, and Nurmatov J. T. "Heat Processing and Change of Proper Indicators of Basalts." Land Science 2, no. 2 (2020): p1. http://dx.doi.org/10.30560/ls.v2n2p1.
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This paper presents the results of the analysis of the quality of basalts, their heat treatment and studies of changes in the chemical composition of basalts, which leads to a change in the external color of partially processed basalt raw materials (hereinafter referred to as semi-finished product). The results of a study of purified basalt from slime, impurities and hydroxides, changes in the chemical composition of basalt rock are presented.
 The prospects of heat treatment of a semi-finished product and obtaining multi-colored products from mineral raw materials is shown. It was found that the optimal firing temperature of the semi-finished product, the possible options for changing the external color and the criterion points of the thermal effect at which the basalt semi-finished product changes the external shade.
 These statements are of great scientific and practical interest in the fact that during the heat treatment of a semifinished product, basalt easily overheats and gradually acquires a different color, which occurs to a liquids temperature and allows the future to plan to obtain high-quality multi-colored products from basalts, for example, products for design.
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Abrahamsen, Niels, and Regin Waagstein. "Magnetic logs from the Lopra-1/1A and Vestmanna-1 wells, Faroe Islands." Geological Survey of Denmark and Greenland (GEUS) Bulletin 9 (May 31, 2006): 41–49. http://dx.doi.org/10.34194/geusb.v9.4857.
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Susceptibility measurements from cores (representing basalt, lapilli-tuffs and tuffs) and magnetic logs from the Lopra-1/1A well are presented. The basalts fall into high- and low-susceptibility groups with no overlap. The high-susceptibility basalts (seven cores) have susceptibilities between 4 and 88 ×10–3 SI and consist of basalt with < 1% vesicles from thick massive units. The low-susceptibility basalts are intergranular, intersertal or hypocrystalline and contain no or very little (< 1%) visible magnetite, are generally more altered than the high-susceptibility basalts and have susceptibilities in the range from 0.6 to 1.4 × 10–3 SI (seven cores). The susceptibility of ten volcaniclastites of lapilli-tuff or tuff varies from 0.4 to 3.8 × 10–3 SI. The cores from the Lopra-1/1A well reveal a bimodal distribution of magnetic susceptibility. Low susceptibilities ranging from 0.4 to 4 are characteristic of altered basalts poor in magnetite, lapilli-tuffs and tuffs. Thus single measurements of susceptibility are of little use in discriminating between these three types of rock. Susceptibility logs from the Lopra-1/1A well show that the variation below 3315 m distinguishes clearly between volcaniclastics (hyaloclastites) with low and fairly constant susceptibility and basalt beds of between 5 and 10 m thickness (with high susceptibility). The volcaniclastics comprise some 60–70% of the sequence between 3315 and 3515 m with the maximum continuous sediment layer being 80 m thick. A 1½ m core of solid basalt at 2381 m and sidewall cores of basalt from the Lopra1/1A well have a mean susceptibility of 22.1 ± 3.5 × 10–3 SI (standard deviation (σ) = 23.6, number of samples (N) = 46), while samples of hyaloclastite (lapilli-tuff and tuff) have a mean susceptibility of 0.85 × 10–3 SI (σ = 0.39, N = 17). The mean values of the rock magnetic parameters for 303 basalt plugs from the Vestmanna-1 well are: Qave = 13.3 ± 0.6 (σ = 11), Save = 11.8 ± 0.6 × 10–3 SI (σ = 11) and Jave = 4.64 ± 0.25 A/m (σ = 4.4). The reversely polarised, lowermost (hidden) part of the c. 4½ km thick lower basalt formation correlates with Chron C26r. The upper (exposed) part of the lower basalt formation correlates with Chrons C26n, C25r and C25n and the more than 2.3 km thick middle and upper basalt formations correlate with Chron C24n.3r.
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Streck, Martin J., Vanessa M. Swenton, William McIntosh, Mark L. Ferns, and Matt Heizler. "Columbia River Rhyolites: Age-Distribution Patterns and Their Implications for Arrival, Location, and Dispersion of Continental Flood Basalt Magmas in the Crust." Geosciences 13, no. 2 (2023): 46. http://dx.doi.org/10.3390/geosciences13020046.
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Columbia River province magmatism is now known to include abundant and widespread rhyolite centers even though the view that the earliest rhyolites erupted from the McDermitt Caldera and other nearby volcanic fields along the Oregon–Nevada state border has persisted. Our study covers little-studied or unknown rhyolite occurrences in eastern Oregon that show a much wider distribution of older centers. With our new data on distribution of rhyolite centers and ages along with literature data, we consider rhyolites spanning from 17.5 to 14.5 Ma of eastern Oregon, northern Nevada, and western Idaho to be a direct response to flood basalts of the Columbia River Basalt Group (CRBG) and collectively categorize them as Columbia River rhyolites. The age distribution patterns of Columbia River rhyolites have implications for the arrival, location, and dispersion of flood basalt magmas in the crust. We consider the period from 17.5 to 16.4 Ma to be the waxing phase of rhyolite activity and the period from 15.3 to 14.5 Ma to be the waning phase. The largest number of centers was active between 16.3–15.4 Ma. The existence of crustal CRBG magma reservoirs beneath rhyolites seems inevitable, and hence, rhyolites suggest the following. The locations of centers of the waxing phase imply the arrival of CRBG magmas across the distribution area of rhyolites and are thought to correspond to the thermal pulses of arriving Picture Gorge Basalt and Picture-Gorge-Basalt-like magmas of the Imnaha Basalt in the north and to those of Steens Basalt magmas in the south. The earlier main rhyolite activity phase corresponds with Grande Ronde Basalt and evolved Picture Gorge Basalt and Steens Basalt. The later main phase rhyolite activity slightly postdated these basalts but is contemporaneous with icelanditic magmas that evolved from flood basalts. Similarly, centers of the waning phase span the area distribution of earlier phases and are similarly contemporaneous with icelanditic magmas and with other local basalts. These data have a number of implications for long-held notions about flood basalt migration through time and the age-progressive Snake River Plain Yellowstone rhyolite trend. There is no age progression in rhyolite activity from south-to-north, and this places doubt on the postulated south-to-north progression in basalt activity, at least for main-phase CRBG lavas. Furthermore, we suggest that age-progressive rhyolite activity of the Snake River Plain–Yellowstone trend starts at ~12 Ma with activity at the Bruneau Jarbidge center, and early centers along the Oregon–Nevada border, such as McDermitt, belong to the early to main phase rhyolite identified here.
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Kulieva, Dilafruz, and Mavlon Avezov. "Prospects of using basalt fibers in light industry." E3S Web of Conferences 390 (2023): 05016. http://dx.doi.org/10.1051/e3sconf/202339005016.
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The paper considers the use of basalt ore - natural raw materials of volcanic origin - in Uzbekistan, as well as the wide use of basalt fibers in various sectors of the economy and their further prospects. Basalt rocks are raw materials for production of fibers and ultrafine fibers, belong to magmatic rocks and possess high natural chemical and thermal stability. Basalt rocks are single-component raw materials that have been enriched, melted and homogenized by ancient volcanic activity. However, the main energy input for the primary melting of basalts was carried out by nature. Basalt is a natural raw material ready for fiber production. The article describes the technological process from extraction of fibers from basalt rocks to their spinning and weaving, obtaining finished fabrics. Laboratory analyses to determine their resistance to tearing, stretching and compression are conducted. The possibility of sewing work clothes from basalt fabrics is considered.
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Shao, Yumeng, Danping Yan, Liang Qiu, Hongxu Mu, and Yi Zhang. "Late Permian High-Ti and Low-Ti Basalts in the Songpan–Ganzi Terrane: Continental Breakup of the Western Margin of the South China Block." Minerals 12, no. 11 (2022): 1391. http://dx.doi.org/10.3390/min12111391.
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Although the Emeishan Large Igneous Province (ELIP) has been thoroughly researched, the role of the ELIP in the tectonics of the Songpan–Ganzi extensional basin in the eastern Tibetan Plateau has long been argued without any corroborated and robust evidence. We have investigated the basalt succession of the Dashibao Formation along Xindianzi and Xuecheng sections in the southeast margin of the Songpan–Ganzi Terrane (SGT). New SIMS zircon U-Pb ages and geochemical features of the Dashibao Formation are reported in this paper. Zircons of basalt sample XDZ02-1 yielded a weighted mean age of 259.1 ± 1.66 Ma, which is in alignment with the period when the main eruption of the ELIP occurred. Zircons from two tuff samples XDZ05-1 and XC05-2, overlying the basalt succession, were dated at 251.8 ± 1.57 Ma and 251.5 ± 0.27 Ma, respectively. These new dating results revealed a ~10 Ma eruption for the Dashibao basalts. The Dashibao basalts are geochemically classified into alkaline basalts (Group 1) and tholeiitic basalts (Group 2), which are a part of the Emeishan basalt. We thus propose that the Dashibao basalts erupted in a continental rift setting, located at the margin of the ELIP. The temporal and spatial coincidence of the Dashibao basalt, ELIP, and continental rifting in the western margin of the South China Block suggest that the continental breakup is a response to the Permian mantle plume that triggered the separation of the SGT in the eastern Tibetan Plateau.
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Lambert, R. StJ, V. E. Chamberlain, and J. G. Holland. "Ferro-andesites in the Grande Ronde Basalt: their composition and significance in studies of the origin of the Columbia River Basalt Group." Canadian Journal of Earth Sciences 32, no. 4 (1995): 424–36. http://dx.doi.org/10.1139/e95-036.
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Flows from the Grande Ronde Basalt of the Columbia River Basalt Group include several with the chemical composition of ferro-andesites. These flows have SiO2 > 55%, MgO < 4%, and also have higher Fe/Mg than the average value for Grande Ronde Basalt. They are also distinctly richer in Cs, Rb, K, Ba, La, Ce, Th, and U than the remainder of the Grande Ronde Basalt flows, and possess small negative Eu anomalies. Their Pb isotopic compositions define a mixing line with a negative slope on a 206Pb/204Pb versus 207Pb/204Pb plot. Their Nd isotopic compositions lie between 143Nd/144Nd = 0.51252 and 0.51264, and their Sr isotopic compositions lie between 87Sr/86Sr = 0.7055 and 0.7060. These values define the enriched end of the Columbia River Basalt Group spectrum on a Sr–Nd epsilon diagram (excluding the Saddle Mountains Basalt). These ferro-andesite flows also form a compositional end member of the Columbia River Basalt Group and are sufficiently distinctive to warrant special consideration. We compare them with lavas from other tholeiitic provinces. Petrogenetically, they can be related to the Grande Ronde Basalt low-Mg basalts by plagioclase fractionation, or by clinopyroxene fractionation in partially melted eclogites. However, the situation may not be that simple, as their unique isotopic compositions are closely related to those of parental mantle materials, perhaps thus requiring separate reservoirs and (or) sources. Extending this argument to other parts of the Columbia River Basalt Group suggests that the origin of these basalts may be in a system of comparatively small magma chambers in the uppermost mantle, frequently replenished from a variety of sources.
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Morishita, Tomoaki, Naoto Hirano, Hirochika Sumino, et al. "Alkali basalt from the Seifu Seamount in the Sea of Japan: post-spreading magmatism in a back-arc setting." Solid Earth 11, no. 1 (2020): 23–36. http://dx.doi.org/10.5194/se-11-23-2020.
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Abstract. We present geochemical and 40Ar∕39Ar age data for a peridotite xenolith-bearing basalt dredged from the Seifu Seamount (SSM basalt) in the northeast Tsushima Basin, southwest Sea of Japan. An 40Ar∕39Ar plateau age of 8.33±0.15 Ma (2σ) was obtained for the SSM basalt, indicating that it erupted shortly after the termination of back-arc spreading in the Sea of Japan. The SSM basalt is a high-K to shoshonitic alkali basalt that is characterized by light rare earth element enrichment. The trace element features of the basalt are similar to those of ocean island basalt, although the Yb content is much higher, indicating formation by the low-degree partial melting of spinel peridotite. The Nd, Sr, and Pb isotopic compositions of the SSM basalt differ from those of back-arc basin basalts in the Sea of Japan. The Sr–Nd isotopic composition of the SSM basalt suggests its source was depleted mid-ocean ridge mantle containing an enriched mantle (EM1) component. The SSM basalt was formed in a post-back-arc extension setting by the low-degree partial melting of an upwelling asthenosphere that had previously been associated with the main phase of back-arc magmatism.
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Young, R. W., C. R. Twidale, and J. T. Hutton. "Silcrete and basalt - discussion." Zeitschrift für Geomorphologie 37, no. 1 (1993): 113–15. http://dx.doi.org/10.1127/zfg/37/1993/113.
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Li, Hengxu, Mengqi Gao, Xiaohui Ji, Zhaochong Zhang, Zhiguo Cheng, and M. Santosh. "Machine Learning-Based Tectonic Discrimination Using Basalt Element Geochemical Data: Insights into the Carboniferous–Permian Tectonic Regime of Western Tianshan Orogen." Minerals 15, no. 2 (2025): 122. https://doi.org/10.3390/min15020122.
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Identifying the tectonic setting of rocks is essential for gaining insights into the geological contexts in which these rocks were formed, aiding in tectonic plate reconstruction and enhancing our comprehensive understanding of the Earth’s history. The application of machine learning algorithms helps identify complex patterns and relationships between big data that may be overlooked by binary or ternary tectonomagmatic discrimination diagrams based on basalt compositions. In this study, three machine learning algorithms, i.e., Support Vector Machine (SVM), Random Forest (RF), and eXtreme Gradient Boosting (XGBoost), were employed to classify the basalts from seven diverse settings, including intraplate basalts, island arc basalts, ocean island basalts, mid-ocean ridge basalts, back-arc basin basalts, oceanic flood basalts, and continental flood basalts. Specifically, for altered and fresh basalt samples, we utilized 22 immobile elements and 35 major and trace elements, respectively, to construct discrimination models. The results indicate that XGBoost demonstrates the best performance in discriminating basalts into seven tectonic settings, achieving accuracies of 85% and 89% for the altered and fresh basalt samples, respectively. A key innovation of our newly developed tectonic discrimination model is the establishment of tailored models for altered and fresh basalts. Moreover, by omitting isotopic features during model construction, the new models offer broader applicability in predicting a wider range of basalt samples in practical scenarios. The classification models were applied to investigate the Carboniferous to Permian evolution in the Western Tianshan Orogen (WTO), revealing that the subduction of Tianshan Ocean ceased at the end of Carboniferous and the WTO evolved into a post-collisional orogenesis during the Permian.
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Yin, Chengxiang, Jian Chen, Xiaohui Fu, et al. "Petrogenesis of Chang’e-6 Basalts and Implication for the Young Volcanism on the Lunar Farside." Astrophysical Journal Letters 981, no. 1 (2025): L2. https://doi.org/10.3847/2041-8213/adaf20.
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Abstract Mare basalts from lunar farside are pivotal for unraveling lunar nearside-farside dichotomies and global thermal history. The Chang’e-6 (CE-6) mission conducted the first sampling from a young basaltic unit within the Apollo basin on the lunar farside. Here, we performed comprehensive petrological and geochemical analyses on the CE-6 basalt clasts. The CE-6 basalt is a low-titanium basalt (about 5 wt% TiO2) depleted in KREEP components. The absence of olivine, particularly magnesium-rich olivine, suggests that the basaltic magma underwent extensive fractional crystallization. Thermodynamic modeling supports that there may be 10%–20% late-stage cumulates of magma ocean (clinopyroxene and ilmenite) present in the source region of CE-6 basalt. The magma derived from the partial melting of such lunar mantle may undergo fractional crystallization dominated by olivine and clinopyroxene within a shallow magma cg1hamber, followed by eruption. Modeling of the REE pattern further indicates that 3%–7% batch melting of a depleted lunar mantle source, combined with 21%–59% fractional crystallization, achieves the observed REE abundances of CE-6 basalt. The genesis of CE-6 basalt could be attributed to the synergistic influence of a readily fusible mantle source, resulting from the incorporation of late-stage cumulates, and the crust-mantle deformation induced by large impacts. This could serve as a paradigm for the formation of other young basalts on the Moon.
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Das, Aditya, Subham Sarkar, Dwijesh Ray, and Rahul Sirvi. "Columnar Jointing in the Deccan Continental Flood Basalt, India: Implications as a Martian Analogue." Earth and Planetary Science 4, no. 1 (2025): 26–38. https://doi.org/10.36956/eps.v4i1.1652.
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The continental flood basalt on Earth and the extensive flood basalt provinces on Mars are well recognised for their prominent surface manifestation, which offer valuable insights into the planet’s interior activity and evolution. Mars’s volcanic provinces are significantly larger than those on Earth; however, the volcanic landforms, particularly the columnar jointing in basalt flows, show some remarkable morphological resemblances. The Deccan trap basalts are characterised by a tholeiite composition with typical iron‑rich trend similar to that of Martian basalts. Within the Deccan volcanic province, the columnar jointing includes both colonnade and entablature jointing facies with a more or less consistent hexagonality index (XN:1.34), reflecting its maturity index. A higher cooling rate (0.29 °C/h) contributes to the formation of entablature as compared to colonnade. The morphology of the colonnade is influenced by a uniform cooling mechanism corroborated with the liquid water infiltration during the emplacement of lava. Thus, the columnar jointing in basalt provides insights into the paleoenvironment during lava emplacement. The morphology of columnar basalt on Mars is mainly gained through remote sensing and in situ rover observations. The presence of both colonnade and entablature on Martian columnar basalt also indicates that water was likely prevalent, possibly flooding or ponding during the lava’s emplacement. In comparative planetology, incorporating new, potential terrestrial analogue materials remains a top priority to validate orbiter data and to strategise for future planetary exploration.
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Liu, Jin, Lida Luo, Jiali Xu, Xiaoxu Zhu, Guoying Shi, and Qingwei Wang. "The Impact of the Composition on the Properties of Simulated Lunar Mare Basalt Fibers." Materials 17, no. 9 (2024): 2043. http://dx.doi.org/10.3390/ma17092043.
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Lunar mare basalt is recognized as an important in situ resource on the lunar surface. However, the significant compositional variability of lunar mare basalts introduces uncertainties concerning the potential for their use in fabricating fibers and composite materials. This study investigates the impact of different components on the fiber-forming capabilities of mare basalts by simulating the compositions of basalts collected from several well-known lunar missions and then preparing simulated lunar mare basalt fibers. Raman spectroscopy is primarily employed for analysis and characterization, using “peak area normalization” to explore the impact of compositional fluctuations in the simulated lunar mare basalts on the glass network structure. The findings indicate that an increase in the Fe content raises the likelihood of basalt fibers crystallizing. Additionally, Fe3+ is shown to substitute for Si and Al in constructing bridging oxygen bonds in the network structure, albeit reducing the overall polymerization of the network. Meanwhile, Fe2+ acts as a network modifier to enhance the mechanical properties of the fibers.
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Kahle, A., B. Winkler, and A. Radulescu. "Small-angle neutron scattering investigation of the effect of a heat-treatment on the microstructure of porous basalt rocks." Mineralogical Magazine 70, no. 6 (2006): 689–95. http://dx.doi.org/10.1180/0026461067060355.
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AbstractSmall-angle neutron scattering has been used to study the microstructure of natural porous basalt rocks. The effect of temperature on the rock microstructure has been investigated on ‘as received’ and heat-treated basalts. The magnitudes of α, the power-law scattering exponent were between 3 and 4 for the majority of the rocks, indicating a surface fractal structure between the basalt matrix and the pore space. Heat-treated basalts show higher α values, and therefore a smoother pore surface. Internal surface areas were determined for all basalts depending on the thermal history.
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Bhardwaj, Priyanka, Mainak Mitra, and Pranab Kumar Saha. "Interpreter's Corner." Leading Edge 40, no. 8 (2021): 619–25. http://dx.doi.org/10.1190/tle40080619.1.
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Basaltic reservoirs have produced hydrocarbon from Yurihara Field in Japan, Quiko Depression in China, and Padra Field of Cambay Basin and Western Offshore Basin in India. The availability of fractured, altered, and vesicular basalts contributes to reservoir development in this stratigraphic unit. This study is conducted in the Kutch-Saurashtra Basin, located at the western continental margin of the Indian subcontinent wherein, the Deccan basalt, with a thickness range of 200–2500 m, overlies Mesozoic sediments. The Jurassic and Cretaceous sediments constitute the main source rock in the area. Several wells have been drilled through the entire basalt section, and some are hydrocarbon bearing in basalt. The entire basalt section in the study area has been classified into four major units using gamma-ray logs. These units have been further subdivided into individual flows and correlated all over the basin. Analysis shows that the base of an individual basalt flow is massive, and the top is differentially altered. Crossplot analysis of P-impedance and VP/VS ratio carried out on logs delineates a zone of moderately weathered/altered basalt, which is due to spheroidal weathering and calibrated with sidewall cores. These moderately altered zones between two successive flows of basalt are the probable reservoir facies for hydrocarbon accumulation, provided that there is an overlying seal in the form of massive or completely altered basalt. Three-dimensional seismic data in the area show an alternating reflection pattern in the basalt section due to the alternation of massive and weathered basalt. The seismic signature of basalt in the area is similar to that of a sedimentary sequence in any given area. Continuity of the identified individual flows in seismic scale has been propagated over the entire seismic, and subsequent inversion has facilitated the deciphering of the probable hydrocarbon-bearing locales within basalt.
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Hooper, P. R., B. A. Gillespie, and M. E. Ross. "The Eckler Mountain basalts and associated flows, Columbia River Basalt Group." Canadian Journal of Earth Sciences 32, no. 4 (1995): 410–23. http://dx.doi.org/10.1139/e95-035.
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Recent mapping of flows of the Columbia River Basalt Group between Lewiston and Pomeroy, southeast Washington, places the chemically distinctive Shumaker Creek flow as a new member between the Frenchman Springs and Roza members of the Wanapum Basalt. This leaves the Eckler Mountain Formation composed of only the Robinette Mountain and Dodge chemical types, with the Lookingglass flow forming the base of the overlying Wanapum Basalt. One Robinette Mountain flow and five separate flows of Dodge composition are recognized and traced across the Blue Mountains Anticline of southeast Washington and northeast Oregon. The aerial distribution of the flows is used to constrain the onset of deformation in the Blue Mountains area between the Hite and Limekiln faults. A series of open east–west folds formed during late Wanapum and Saddle Mountains time, cut by northeast-trending faults with left-lateral strain. Chemical variations between Eckler Mountain, Grande Ronde, and Wanapum Basalt flows require different source components. But between the Eckler Mountain flows the variation of most chemical parameters is consistent with fractional crystallization in the crust and can be modeled for major and trace elements. An exception is the behaviour of Cr and Zr/Y between the Robinette Mountain and Dodge flows, which suggests variable partial melting or possibly olivine accumulation.
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Kurbonov, A., L. Sattorov, B. Kamolov, and O. Rakhimov. "Chemical and mineralogical studies of basalt “Aydarkul”." BIO Web of Conferences 71 (2023): 02040. http://dx.doi.org/10.1051/bioconf/20237102040.
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In the article, the geologic, structural, and mineralogical composition of the “Aydarkul” basalt mine was studied as a result of research, and a complete analysis of the physical and chemical pieces of the basalt rock was given. Based on the results of theoretical and experimental studies, the physical and chemical foundations of pyro- and hydrometallurgical methods of rock processing - basalt raw materials - have been developed. Technological options are proposed that allow obtaining demanded products of various compositions. A schematic diagram of the complex processing of basalt raw materials has been developed, including the processing of waste and by-products, as well as the extraction of accessory materials. The study found that the basalts of the Aydarkul mine can be used in the electric power industry.
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Adams, Steven M., and Gerilyn S. Soreghan. "Producing Dust through Simulated Glacial Abrasion of Basalt Clasts with Implications for Mars." Planetary Science Journal 6, no. 5 (2025): 124. https://doi.org/10.3847/psj/adc9ab.
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Abstract Multiple processes have been proposed for the genesis of dust on Mars, including volcanic eruptions, eolian abrasion, bolide impacts, and glacial grinding. Atmospheric dust has a significant impact on climate that is heavily dependent on the particle size distribution (PSD) of the dust. Therefore, we ask, do different dust-generating mechanisms produce different dust PSDs and, consequently, different impacts on the climate? Glacial grinding is the erosive process of clasts embedded in the base of a glacier sliding across bedrock or subglacial sediment. We use basalt clasts as analogs to assess sediment production via experimental glacial grinding. We cut small (3 cm), flat- and point-tipped fabricated clasts from five distinct basalts and used a novel experimental apparatus to abrade them across a basal rock slab representing bedrock. Pointed clasts generally produced more sediment than flat clasts, as did clasts with vesicular textures compared to those with nonvesicular textures. The resulting PSDs show that most dust samples exhibit a primary mode, between 20 and 50 μm. These results indicate a tendency toward silt production from rock-on-rock grinding of basalt, akin to the conditions at the base of a wet-based glacier. Results were compared to sediment PSDs from other potential dust-producing mechanisms. Simulated glacial grinding of basalt generates proportionally ∼50% more fine dust (<2.5 μm) than simulated eolian abrasion of basalt sand. Results from these experiments suggest that if widespread wet-based glaciation existed on Mars, the dust produced would have influenced the climate, although the net radiative effect is unknown.
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Reidel, Stephen P., and D. Brent Barnett. "Igneous Rock Associations 27. Chalcophile and Platinum Group Elements in the Columbia River Basalt Group: A Model for Flood Basalt Lavas." Geoscience Canada 47, no. 4 (2020): 187–214. http://dx.doi.org/10.12789/geocanj.2020.47.166.
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The Columbia River Basalt Group is the youngest and best preserved continental Large Igneous Province on Earth. The 210,000 km3 of basaltic lavas were erupted between 16.6 and 5 Ma in the Pacific Northwest, USA. The peak of the eruptions occurred over a 700,000-year period when nearly 99% of the basalts consisting of the Steens, Imnaha, Picture Gorge, Grande Ronde and Wanapum Basalts were emplaced. In this study we examined the Platinum Group Elements (PGEs) Pt and Pd, and the chalcophile elements Cu and Zn in the Columbia River Basalt Group. The presence of Pt, Pd and Cu in the compositionally primitive Lower Steens, Imnaha and Picture Gorge Basalts suggests that the Columbia River Basalt Group magma was a fertile source for these elements. The PGEs are contained mainly in sulphides in the earliest formations based on their correlation with immiscible sulphides, sulphide minerals and chalcophile elements. Grande Ronde, Wanapum and Saddle Mountains Basalts are depleted in PGEs and chalcophile elements compared to earlier formations. Sulphur was saturated in many flows and much of it probably came from assimilation of cratonic rock from a thinned lithosphere. We propose a model where the presence or absence of PGEs and chalcophile elements results primarily from the interaction between an advancing plume head and the crust/lithosphere that it encountered. The early lavas erupted from a plume that had little interaction with the crust/lithosphere and were fertile. However, as the plume head advanced northward, it assimilated crustal/lithospheric material and PGE and chalcophile elements were depleted from the magma. What little PGE and chalcophile elements remained in the compositionally evolved and depleted Grande Ronde Basalt flows mainly were controlled by substitution in basalt minerals and not available for inclusion in sulphides.
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Zhang, Cheng, Jianping Chen, Yiwen Pan, et al. "Geomorphology, Mineralogy, and Chronology of Mare Basalts in the Oceanus Procellarum Region." Remote Sensing 16, no. 4 (2024): 634. http://dx.doi.org/10.3390/rs16040634.
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Mare basalts on the lunar surface are tangible expressions of the complex thermal evolution and geological processes that have occurred within the lunar interior. These basaltic manifestations are highly important because they provide invaluable insights into lunar geological evolution. Notably, the Oceanus Procellarum region, which is renowned for its extensive and long-lasting basaltic volcanism, is a premier location to investigate late-stage lunar thermal evolution. The primary aim of this research is to elucidate the geomorphological, compositional, and temporal attributes that define the mare basalts within the Oceanus Procellarum region. To achieve this aim, we comprehensively analyzed the geomorphological features present within the region, leveraging Kaguya/SELENE TC images and digital elevation models. Specifically, these geomorphological features encompass impact craters, wrinkle ridges, sinuous rilles, and volcanic domes. Subsequently, we thoroughly examined the mineralogical attributes of basalts in the Oceanus Procellarum region, leveraging Kaguya/SELENE MI data and compositional map products. To more accurately reflect the actual ages of the mare basalts in the Oceanus Procellarum region, we carefully delineated the geological units within the area and employed the latest crater size-frequency distribution (CSFD) technique to precisely determine their ages. This refined approach allowed for a more comprehensive and accurate understanding of the basaltic rocks in the study area. Overall, our comprehensive study included an in-depth analysis of the volcanic activity and evolution of the Oceanus Procellarum region, along with an examination of the correlation between the mineralogical composition and ages of mare basalts. The findings from this exhaustive investigation reveal a definitive age range for basalt units within the Oceanus Procellarum region from approximately 3.69 Ga to 1.17 Ga. Moreover, the latest mare basalts that formed were pinpointed north of the Aristarchus crater. Significantly, the region has experienced at least five distinct volcanic events, occurring approximately 3.40 Ga, 2.92 Ga, 2.39 Ga, 2.07 Ga, and 1.43 Ga, leading to the formation of multiple basalt units characterized by their unique mineral compositions and elemental abundances. Through the application of remote sensing mineralogical analysis, three primary basalt types were identified: low-titanium, very-low-titanium, and intermediate-titanium basalt. Notably, the younger basalt units exhibit an elevated titanium proportion, indicative of progressive olivine enrichment. Consequently, these younger basalt units exhibit more intricate and complex mineral compositions, offering valuable insights into the dynamic geological processes shaping the lunar surface.
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Nazarov, Sayfulla, Khasan Razzokov, Gayrat Shirinov, et al. "Investigation of thermal properties and composition on basalts of the Aydarkul deposit by methods DTA/DTG and X-ray diffraction." E3S Web of Conferences 389 (2023): 01023. http://dx.doi.org/10.1051/e3sconf/202338901023.
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To study the applicability of the basalt fiber through various experimental works in thermal and chemical environments, lining heat-insulating materials basis on basalt of Aydarkul deposit were compared and discussed. The identification and study phase pert structures lining heat-insulating materials basis on basalt of Aydarkul deposit used X-ray diffraction analysis. The basalt fiber showed better strength retention than the glass fiber at relatively high temperature. The article studies the endothermic effects of the thermolysis process, which appear at a temperature of 80 ÷240 0C. They show the decomposition of clay impurities or the removal of hygroscopic water contained in rocks. The chemical and mineralogical composition of the basalts of the Aydarkul deposit has been studied by such modern methods as X-ray diffraction and differential thermal analysis methods.
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Japsen, Peter, Morten Sparre Andersen, Lars Ole Boldreel, et al. "Seismic and petrophysical properties of Faroe Islands basalts: the SeiFaBa project." Geological Survey of Denmark and Greenland (GEUS) Bulletin 4 (July 20, 2004): 53–56. http://dx.doi.org/10.34194/geusb.v4.4784.
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Flood basalt-covered basins exist worldwide along continental margins and are now in focus as targets for future hydrocarbon exploration. It is generally difficult to image through the basalt cover by conventional seismic reflection methods, and this is a major challenge to future petroleum exploration offshore the Faroe Islands. Long-offset profiling has proven very successful (White et al. 2003). Surprisingly, however, it is possible to image through kilometre-thick basalt sequences on some conventional profiles. Details of basalt stratigraphy are revealed on old, reprocessed seismic profiles as well as on recently acquired profiles, even though the imaging may be unsuccessful on nearby profiles (e.g. Boldreel & Andersen 1993). This stresses the need for a better understanding of the acoustic and other physical properties of basalt as well as of the degree of three-dimensional heterogeneity. The SeiFaBa project (Seismic and petrophysical properties of Faroes Basalt, 2002–2005) is funded by the Sindri Group as part of the programmes for licensees within the Faroese offshore area, and addresses these issues with special focus on the subaerially extruded flood basalts of the Faroe Islands (cf. Japsen et al. in press).
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Kanayama, Kenji. "Basalt Fibers." Seikei-Kakou 33, no. 4 (2021): 117–20. http://dx.doi.org/10.4325/seikeikakou.33.117.
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Rakovan, John. "Pillow Basalt." Rocks & Minerals 80, no. 4 (2005): 287. http://dx.doi.org/10.3200/rmin.80.4.287-287.
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ELGHAWABI, SAMIR H., RAWIA E. ZEWER, SAMIHA M. IBRAHIM, and SAMIR R. SELIM. "Basalt Pneumoconiosis." Occupational Medicine 35, no. 4 (1985): 131–33. http://dx.doi.org/10.1093/occmed/35.4.131.
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Mills, Andrea, and Hamish Sandeman. "Lithostratigraphy and lithogeochemistry of Ediacaran alkaline basaltic rocks of the Musgravetown Group, Bonavista Peninsula, northeastern Newfoundland, Canada: an extensional volcanogenic basin in the type-Avalon terrane." Atlantic Geology 57 (August 5, 2021): 207–34. http://dx.doi.org/10.4138/atlgeol.2021.010.
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Volcanic rocks of the Ediacaran Musgravetown Group on Bonavista Peninsula, Avalon terrane, Newfoundland, include basal ca. 600 Ma calc-alkaline basalt succeeded by continental tholeiite and alkaline rhyolite of the ca. 592 Ma Plate Cove volcanic belt (Bull Arm Formation), indicating a change from subduction-related to extensionrelated tectonic regimes during that interval. Alkalic basalts on northeastern (Dam Pond area) and southwestern (British Harbour area) Bonavista Peninsula occur below and above, respectively, the ca. 580 Ma glacial Trinity facies. Dam Pond basalt occurs in a structural dome intercalated with and flanked by fine-grained, siliciclastic deposits (Big Head Formation) overlain by Trinity facies. The British Harbour basalt occurs above the Trinity facies, in an upward- coarsening sandstone sequence (Rocky Harbour Formation) overlain by red beds of the Crown Hill Formation (uppermost Musgravetown Group). The Rocky Harbour and Big Head formations are likely stratigraphically interfingered proximal and distal deposits, respectively, derived from erosion of the Bull Arm Formation and older Avalonian assemblages.The Big Head basalts have lower SiO2, Zr, FeOT, P2O5, TiO2 and higher Mg#, Cr, V, Co and Ni contents, and are therefore more primitive than the more FeOT-, TiO2-, and P2O5-rich British Harbour basalts. Large-ionlithophile and rare-earth-element concentrations and ratios indicate that both suites originated from low degree partial melts of deep, weakly garnet-bearing, undepleted asthenospheric peridotite sources, with magma conduits likely focused along regional extensional faults. The protracted and episodic extension-related volcanic activity is consistent with a geodynamic setting that evolved from a mature arc into extensional basins with slowly waning magmatism, possibly involving slab rollback and delamination followed by magmatic underplating. The duration and variation of both volcanism and sedimentation indicate that the Musgravetown Group should be elevated to a Supergroup in order to facilitate future correlation of its constituent parts with other Avalonian basins.
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Kadyrova, Zulayho, Shokhista Niyazova, Munira Kazakova, and Aman Purkhanatdinov. "Physico-chemical studies of Arvaten basalt for the production of mineral fiber." E3S Web of Conferences 431 (2023): 06027. http://dx.doi.org/10.1051/e3sconf/202343106027.
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The article carried out complex studies to determine the chemical, chemical-mineralogical composition, acidity and viscosity modules of basalt from the Arvaten deposit. It has been established that the basalts of this deposit can be used as a raw material for the production of stone casting materials, in the form of mineral wool, as well as basalt fiber with corrective additives.
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Nelson, Faye E., René W. Barendregt, and Mike Villeneuve. "Stratigraphy of the Fort Selkirk Volcanogenic Complex in central Yukon and its paleoclimatic significance: Ar/Ar and paleomagnetic data." Canadian Journal of Earth Sciences 46, no. 5 (2009): 381–401. http://dx.doi.org/10.1139/e09-025.
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Brunhes, Matuyama, Kaena, and Mammoth age basaltic lava flows (Tertiary–Quaternary Selkirk Volcanics) were sampled in west-central Yukon. The mean characteristic remanent magnetization (ChRM) direction of the flows sampled in this and previous studies has a declination of 348.7° and an inclination of 70.8° (n = 42, k = 99.6, α95 = 2.2°) (all on lower hemisphere). The time range represented in this study (ca. 3.25 to ca. 0.004 Ma) is great enough to have confidently averaged secular variation. Sediment associated with the basalt has a mean declination of 7.6° and inclination of 78.8° (n = 5, k = 5.6, α95 = 35.7°). A new 40Ar–39Ar date on the reversely magnetized basal basalts at Ne Ch’e Ddhäwa places the eruption in the Mammoth subchron of the Gauss Normal Chron. The newly dated basal basalt at Ne Ch’e Ddhäwa precedes the initial continental glaciation in Yukon and is older than the Fort Selkirk vent (Lower Mushroom), which was previously thought to be the oldest eruption at Fort Selkirk Volcanic Complex (FSVC). This basal flow at Mushroom is dated at 1.82 ± 0.03 Ma and the uppermost flow is reproducibly dated at 1.36 ± 0.04 Ma. Till on the flanks of a subglacial volcanic mound called Ne Ch’e Ddhäwa (informal) is older than previously thought; its reverse magnetization indicates an Early Pleistocene age rather than the Reid glaciation, which falls during the Brunhes Normal Chron. The paleomagnetism of Tertiary–Quaternary Selkirk Volcanics outcrops outside the FSVC was studied for the first time. The ChRM direction of basalt at the northern edge of the northern Cordillera volcanic province agrees with FSVC directions, suggesting that this flow reflects the same period of volcanism. This suggests that an Eocene K–Ar date, previously thought to be unreliable, may well be correct.
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Hussain, M. Faruque, Md Shofiqul Islam, and Mithun Deb. "Petrological and geochemical study of the Sylhet trap basalts, Shillong plateau, N.E. India: Implications for petrogenesis." European Journal of Geosciences 2, no. 1 (2020): 01–18. http://dx.doi.org/10.34154/2020-ejgs-0201-1-18/euraass.
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Sylhet Traps exposed along the southern margin of Shillong plateau, Northeast India are subalkaline tholeiitic basalts. The basalts are generally massive but occasionally contain large amygdules of zeolites and chalcedony. Microscopically, some basalts show porphyritic texture with olivine phenocrysts. Phenocryst assemblage of plagioclase ± clinopyroxene ± olivine implies crystallization at shallow level. SEM-EDX analysis shows occurrences of spinel with Ni and Cr within the basalts therefore indicating partial melting of the subcontinental lithospheric mantle as the possible source materials for the basalts. The multi-element plot for the basalts shows two distinct trends: one with significant enrichment of LILE and depletion of HFSE and plot similar to OIB (Type 1) while the other trends are chara cterized by slight enrichment of LILE and negative anomalies at Nb, P and Ti (Type 2). Chondrite-normalized REE patterns for Type 1 basalt shows very high enrichment of LREE and a strong right dip HREE pattern and also plots similar to typical OIB while Type 2 show a slight enrichment of LREE over HREE with small Eu anomaly. The geochemical signatures suggest crustal contamination by plume-derived magma produced by low degree of partial melting for Type 1 basalt. Type 2 basalt was produced by partial melting of subcontinental lithospheric mantle, which may be triggered by plume upwelling.
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Landing, Ed, Georgia Pe-Piper, William SF Kidd, and Karem Azmy. "Tectonic setting of outer trench slope volcanism: pillow basalt and limestone in the Taconian orogen of eastern New York." Canadian Journal of Earth Sciences 40, no. 12 (2003): 1773–87. http://dx.doi.org/10.1139/e03-076.
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The only pillow basalt in synorogenic sedimentary rocks at the exterior margin of the Taconic orogen in eastern North America is at Stark's Knob in eastern New York. Earlier reported as extrusive into allochthonous Ordovician slope and rise facies, this small lens (ca. 125+ m long, 39 m thick) is a fault-bounded block in Upper Ordovician melange under the Taconian frontal thrust. Its N-MORB (normal mid-ocean ridge basalt) basalt geochemistry and spinel composition are characteristic of oceanic ridge settings at a water depth of 2 km or more. Abundant limestone lenses on pillows and lava shelves within pillows yielded a middle Late Ordovician gastropod. The limestones are reconciled with this extrusion depth and with limited early Paleozoic pelagic carbonate production by lime mud transport from the Laurentian platform or abiotic carbonate precipitation with sea-water heating during basalt extrusion. A genetic relationship between the parautochthonous Stark's Knob basalts and the allochthonous Jonestown volcanics in slope and rise facies of the Hamburg klippe, eastern Pennsylvania, is likely. Both are Ordovician MORB basalts that reflect volcanism on the subducting outer trench slope prior to the Taconic arc Laurentia collision. Taconic orogenesis may have led to basalt production on the subducting plate by (1) the setting up of orogen-parallel, predominantly strike-slip motion on the subducting slab with MORB basalt generated at offsets in a setting analogous to the Gulf of California or (2) development of faults in a flexure-induced extensional regime. By either process, mafic volcanism appears to be a rare but tectonically significant process on outer trench slopes as continental margins or oceanic plates enter subduction zones.
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Kislov, Evgeniy V., Anna V. Aseeva, Vladislav V. Vanteev, Anton Yurievich Sinyov, and Olga A. Eliseeva. "Naryn-Gol Creek Sapphire Placer Deposit, Buryatia, Russia." Minerals 12, no. 5 (2022): 509. http://dx.doi.org/10.3390/min12050509.
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A new gem corundum occurrence has been discovered in the Naryn-Gol Creek placer of the Dzhida volcanic field (Russia). In this placer deposit, sapphire associates with large crystals of garnet, spinel, augite, olivine, enstatite, ilmenite, Ti-magnetite, and alkali feldspar. Such a combination of minerals is typical for the placer deposits associated with alkali basalts widely distributed in Southeastern Asia and Australia. We have also found sapphire crystals in phonotephrites of the nearby Cenozoic alkali-basalt paleovolcano Barun Khobol Pravyi, and in basalt sample and trachybasalt from the valley flood basalts. The chemical composition of sapphire is generally typical for ‘basalt’ corundum: it is rich in Fe, and depleted in Ti and Cr. The δ18O SMOW values of corundum and related megacrysts range from 4.6 to 6.8 ‰, thus corresponding to the isotopic signature of igneous rocks. Etched and corroded surfaces of sapphire and other megacrysts indicate that they are in non-equilibrium with their host alkali basalts. Volatile components, CO2 in particular, played a significant role during sapphire formation as gas inclusions reveal.
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He, Hua Nan, and Wei Dong. "Study on Damaged Reinforced Concrete Beams Strengthened with Basalt Fiber Polymer Sheets." Advanced Materials Research 446-449 (January 2012): 2941–44. http://dx.doi.org/10.4028/www.scientific.net/amr.446-449.2941.
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In practical concrete structures, once reinforced concrete beams serve in case of over cracking or are even damaged due to sudden overloading, it is necessary to repair or strengthened the damaged members for purpose of restoring the structural capacities and keeping the structures working well. At present FRP strengthening technique is one of the most accepted methods available in civil engineering. This paper particularly presents a new FRP material，basal fiber, which is applied to strengthen flexural behaviors of reinforced concrete beams suffering from different amplitudes of cracking damage. Herein, total 4 reinforced concrete beams were tested including one reference beam and three beams strengthened with basalt fiber polymer sheets. The three strengthened beams were preloaded to an expected load and then strengthen by basalt fibers under loading. The test parameters are involved in different pre-loads and layers of basalt fiber sheets. During test some flexural behaviors were obtained in terms of variation of strain in concrete, steel bar and basalt fiber sheet, flexural deflection, collapse loads and the failure modes as well as cracking properties of R.C beams strengthened with basalt fiber sheets. The results of test indicated that flexural behaviors of the beams strengthened under loading with basalt fiber polymer could be improved in different degree with varied initial flexural moment and numbers of basalt fiber.
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Nicholson, Suzanne W., Klaus J. Schulz, Steven B. Shirey, and John C. Green. "Rift-wide correlation of 1.1 Ga Midcontinent rift system basalts: implications for multiple mantle sources during rift development." Canadian Journal of Earth Sciences 34, no. 4 (1997): 504–20. http://dx.doi.org/10.1139/e17-041.
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Magmatism that accompanied the 1.1 Ga Midcontinent rift system (MRS) is attributed to the upwelling and decompression melting of a mantle plume beneath North America. Five distinctive flood-basalt compositions are recognized in the rift-related basalt succession along the south shore of western Lake Superior, based on stratigraphically correlated major element, trace element, and Nd isotopic analyses. These distinctive compositions can be correlated with equivalent basalt types in comparable stratigraphic positions in other MRS localities around western Lake Superior. Four of these compositions are also recognized at Mamainse Point more than 200 km away in eastern Lake Superior. These regionally correlative basalt compositions provide the basis for determining the sequential contribution of various mantle sources to flood-basalt magmatism during rift development, extending a model originally developed for eastern Lake Superior. In this refined model, the earliest basalts were derived from small degrees of partial melting at great depth of an enriched, ocean-island-type plume mantle source (εNd(1100) value of about 0), followed by magmas representing melts from this plume source and interaction with another mantle source, most likely continental lithospheric mantle (εNd(1100) < 0). The relative contribution of this second mantle source diminished with time as larger degree partial melts of the plume became the dominant source for the voluminous younger basalts (εNd(1100) value of about 0). Towards the end of magmatism, mixtures of melts from the plume and a depleted asthenospheric mantle source became dominant (εNd(1100) = 0 to +3).
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Lutter, William J., Rufus D. Catchings, and Craig M. Jarchow. "An image of the Columbia Plateau from inversion of high‐resolution seismic data." GEOPHYSICS 59, no. 8 (1994): 1278–89. http://dx.doi.org/10.1190/1.1443685.
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We use a method of traveltime inversion of high‐resolution seismic data to provide the first reliable images of internal details of the Columbia River Basalt Group (CRBG), the subsurface basalt/sediment interface, and the deeper sediment/basement interface. Velocity structure within the basalts, delineated on the order of 1 km horizontally and 0.2 km vertically, is constrained to within ±0.1 km/s for most of the seismic profile. Over 5000 observed traveltimes fit our model with an rms error of 0.018 s. The maximum depth of penetration of the basalt diving waves (truncated by underlying low‐velocity sediments) provides a reliable estimate of the depth to the base of the basalt, which agrees with well‐log measurements to within 0.05 km (165 ft). We use image blurring, calculated from the resolution matrix, to estimate the aspect ratio of imaged velocity anomaly widths to true widths for velocity features within the basalt. From our calculations of image blurring, we interpret low velocity zones (LVZ) within the basalts at Boylston Mountain and the Whiskey Dick anticline to have widths of 4.5 and 3 km, respectively, within the upper 1.5 km of the model. At greater depth, the widths of these imaged LVZs thin to approximately 2 km or less. We interpret these linear, subparallel, low‐velocity zones imaged adjacent to anticlines of the Yakima Fold Belt to be brecciated fault zones. These fault zones dip to the south at angles between 15 to 45 degrees.
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Kahn, Maureen, Annia K. Fayon, and Basil Tikoff. "Constraints on the post-orogenic tectonic history along the Salmon River suture zone from low-temperature thermochronology, western Idaho and eastern Oregon." Rocky Mountain Geology 55, no. 1 (2020): 27–54. http://dx.doi.org/10.24872/rmgjournal.55.1.27.
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ABSTRACT The abrupt boundary between accreted terranes and cratonic North America is well exposed along the Salmon River suture zone in western Idaho and eastern Oregon. To constrain the post-suturing deformation of this boundary, we assess the cooling history using zircon and apatite (U–Th)/He thermochronology. Pre-Miocene granitic rocks, along a regional transect, were sampled from accreted terranes of the Blue Mountains Province to cratonic North America (Idaho batholith). Each sample was taken from a known structural position relative to a paleotopographic surface represented by the basal unit of the Miocene Columbia River basalts. An isopach map constructed for the Imnaha Basalt, the basal member of the Columbia River Basalt Group (CRBG), confirms the presence of a Miocene paleocanyon parallel to the northern part of Hells Canyon. The (U–Th)/He zircon dates indicate mostly Cretaceous cooling below 200°C, with the ages getting generally younger from west to east. The (U–Th)/He apatite dates indicate Late Cretaceous–Paleogene cooling, which post-dates tectonism associated with the western Idaho shear zone (WISZ). However, (U–Th)/He apatite dates younger than the Imnaha Basalt, with one date of 3.4 ± 0.6 Ma, occur at the bottom of Hells Canyon. These young (U–Th)/He apatite dates occur along the trend of the Miocene paleocanyon, and cannot be attributed to local exhumation related to faults. We propose that burial of Mesozoic basement rocks by the Columbia River basalts occurred regionally. However, the only samples currently exposed at the Earth’s surface that were thermally reset by this burial were at the bottom of the Miocene paleocanyon. If so, exhumation of these samples must have occurred by river incision in the last 4 million years. Thus, the low-temperature thermochronology data record a combination of Late Cretaceous–Paleogene cooling after deformation along the WISZ that structurally overprinted the suture zone and Neogene cooling associated with rapid river incision.
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Siringoringo, L. P., B. Sapiie, A. Rudyawan, and I. G. B. E. Sucipta. "The distribution of vesicular structures in Sukadana Basalt, East Lampung, Indonesia, and its significance for the geological structure interpretation." IOP Conference Series: Earth and Environmental Science 1373, no. 1 (2024): 012043. http://dx.doi.org/10.1088/1755-1315/1373/1/012043.
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Abstract The characteristics of the geological structures controlling the presence of Sukadana basalt on the Earth’s surface are still an enigma. Therefore, this study was conducted to determine the probable types of geological structures and their orientations that could control the occurrence of Sukadana Basalt lava on the Earth’s surface. To seek answers to this problem, this study utilized vesicular structure data from Sukadana Basalt based on 13 rock samples from 13 observation points. We measured the diameter of the vesicular and the sum of the megascopic vesicular per cm2 for every sample. We used a scale of 1-5, where 1-2 indicated as small-low intensity vesicular, 3 indicated as medium-middle intensity vesicular, and 4-5 indicated as large-high intensity vesicular. it was found that there are three groups of vesicular that were developed in Sukadana Basalts: small-low, medium-middle, and large-high groups. This study gives information that there are three fracturures including two normal faults at the northern and southern parts of Sukadana Basalt and one fisurre in the middle of Sukadana basalt. The normal fault at the southern part of Sukadana Basalt has the widest fault core spacing and the fissure at the middle of Sukadana Basalt has the narrowest fissure core spacing. All groups show northwest-southeast striking fractures. This study will provide a new point of view that in interpreting subsurface geological structures can use primary structure characteristics data, especially vesicular structures.
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Dhiman, Anshul. "Micromorphology of basalt alterite and its implications on the geological processes during quiescence period of the Deccan volcanism, Kharghar hill, Maharashtra, India." Indian Association of Sedimentologists 41, no. II (2024): 31–38. https://doi.org/10.51710/jias.v41iii.377.
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Palaeoweathering unearths hidden mysteries of the previously weathered (paleo) surfaces. Researchers have shown that each mineral weathers/alters in a particular manner and is process-specific. Micromorphology is the most reliable and well-established technique to identify process-specific features imparted in an alterite under a given set of conditions. The Indian Deccan traps form one of the world’s largest flood basalt volcanic provinces and has numerous exposures. Notwithstanding, systematic micromorphological studies of Deccan flood basalts are lacking compared to such flood basalts of global occurrences. The episodic nature of Deccan volcanism provided subsequent phases of interaction with the Earth’s surface processes, thereby making the basalt alterites an ideal repository of surficial conditions and subsequent duration. Deccan basalt alterite exposed in the Kharghar hill of Mumbai (Maharashtra) has been selected for detailed micromorphology. Micromorphological results from the top to bottom of >70 cm thick, buried basalt alterite show changes in specific pattern of primary mineral alteration, formation of secondary minerals, development and patterns of secondary porosity. For example, the top of studied alterite (i.e. top 30 cm) has irregular, speckled and patchy patterns of mineral alteration, intramineral secondary pores, dominance of secondary products and only isolated alteromorphs that too with large elongate patches. Whereas towards the bottom (i.e. below 30 cm), the alterite shows planar patterns of mineral alteration, which is preceded at places by a linear/speckled pattern and most distinct is the dominance of intermineral pore system connected with transmineral fractures. Therefore, the basalt alterite can be subdivided from top to bottom into two distinct layers namely, alloterite and isalterite. This distinction significantly indicates a change in process with time as well as duration of basalt interaction with then prevailing surficial conditions. Thus, it can be concluded that alteroplasmation was progressively and gradually replaced with pedoplasmation resulting in dominance of supergene processes over hypogene processes.
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Linthout, K. "Provenance of the Roman basalt stone at Kotterbos (Lelystad, the Netherlands): A geoarchaeological study based on petrographic and geochemical analysis, and comparison with a synthesis of basalt stones along the northern Limes." Netherlands Journal of Geosciences - Geologie en Mijnbouw 94, no. 4 (2015): 387–97. http://dx.doi.org/10.1017/njg.2014.45.
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AbstractA solitary unprocessed, 26-cm basalt stone recently found at the Roman (69 AD) site at Kotterbos (Lelystad, the Netherlands), situated 40 km north of the Limes, has been examined petrographically and geochemically. The rock is similar to previously investigated Roman basalt stones and blocks from the Limes in the province of Utrecht. All are alkali olivine basalts and basanites, which are also the dominant rock types in the nearby volcanic hinterland in Germany. On the basis of 23 criteria, including all major and minor elements plus a selection of trace elements, the Kotterbos stone correlates with a distinctive subgroup of Limes basalts. This subgroup is characterised by relatively high Mg# and low TiO2 wt% values, as opposed to the other subgroup with lower Mg# and higher TiO2 wt% values. It is argued that the high Mg#–low TiO2 subgroup and the Kotterbos basalt have common geological provenance(s). Five basalt bodies in the hinterland match the criteria of this subgroup, and might be considered as locations of provenance. Of these five, only Rolandsbogen, located next to an ideal anchorage on the west bank of the Rhine, about 12 km upstream from Bonn, can also conform to sensible Roman demands concerning effective logistics and military safety. Consequently, Rolandsbogen is the most likely site of provenance for the high Mg#–low TiO2 subgroup, which includes the Kotterbos basalt. It is argued that the Kotterbos stone is not a rock that somehow got separated from a shipment of building stones to the northern Limes; rather, it is speculated that the stone was picked up as a stray cobble near the basalt body and taken onboard a Roman vessel moored at the Rolandsbogen anchorage.
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Venkatesan, T. R., K. Pande, and K. Gopalan. "40Ar-39Ar Darting of Deccan Basalts." Journal Geological Society of India 27, no. 1 (1986): 102–9. http://dx.doi.org/10.17491/jgsi/1986/270102.
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Abstract The feasibility of dating igneous rocks by the 40Ar-39Ar method in India using the Apsara nuclear reactor at BARC, Bombay is reported, based on measurements on two tholeiitic basalts and one alkali basalt associated with the Deccan volcanism. The ages of the tholeiitic basalts are 71±4 Ma and 65±4 Ma, respectively and that of the alkali basalt is 682 Ma. Apart from the low neutron flux requiring long irradiation times, the neutron fluence within the sample irradiation volume is somewhat anisotropic. The latter needs to be minimised to achieve the higher precision the method is capable of.
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Sethna, S. F., and Priya Javeri. "Geology and Petrochemistry of the Deccan Spilitic Basalts at and around Daman, India." Journal Geological Society of India 53, no. 1 (1999): 59–69. http://dx.doi.org/10.17491/jgsi/1999/530108.
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Abstract Major, trace and rare earth element analyses of spilitic basalts and some dolerite dykes and microprobe mineral analyses of a spilitic basalt are reported. It is postulated that these rocks represent subaqueous flows erupted under fairly shallow water which was insufficient for complete spilitisation of the basalt. The process of metasomatism under subaqueous conditions is considered to have been responsible for the alteration of tholeiite to spilite.
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Kazakova, M. N., A. A. Eminov, and I. K. Shokоsimov. "CHEMICAL-MINERALOGICAL STUDY OF BASALT AND SERPENTINITE FOR OBTAINING MINERAL FIBER." Steklo i Keramika, no. 16 (April 2023): 40–45. http://dx.doi.org/10.14489/glc.2023.04.pp.040-045.
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The article presents the results of studies on the chemical-mineralogical composition, acidity and viscosity moduli of basalt and serpentinite of the Arvaten deposit. It has been established that the basalts and serpentinites of this deposit can be used as a raw material for the production of stone casting materials, in the form of mineral wool, and with corrective additives are suitable for the production of basalt fiber.
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Mathews, W. H. "Neogene Chilcotin basalts in south-central British Columbia: geology, ages, and geomorphic history." Canadian Journal of Earth Sciences 26, no. 5 (1989): 969–82. http://dx.doi.org/10.1139/e89-078.
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An extensive but generally thin mantle of basalt flows, the Chilcotin Group, covers much of the Interior Plateau of south-central British Columbia. It provides material for dating and for reconstructing the original form of the paleosurface on which it was deposited. K–Ar whole-rock dates demonstrate that several ages of basalt are represented, from Early Miocene (or even Late Oligocene?) to Early Pleistocene, with particularly abundant eruptions about 14–16, 9–6, and 1–3 Ma ago.Basalts of Middle Miocene and later ages, if not the Early Miocene relics as well, clearly rest on land surfaces of low local relief. In places the low-relief surfaces had been incised to depths of 100–200 m and the valleys backfilled with mid-or late Cenozoic sediments prior to burial by the basalts. The low-relief surfaces throughout the area are believed to have been developed close to a common base level, and regional differences in their present elevation are thus largely a product of post-basalt deformation. This is recorded by Miocene or later uplift of the southern Coast Mountains and gentle flexing in parts of the Interior Plateau.Major stream incision to depths of up to 1000 m following uplift provides a convenient, but not infallible, means of distinguishing Chilcotin basalts from mid-Pleistocene and younger "valley basalts."The Chilcotin Group is, for the most part, a small-scale counterpart of the roughly contemporaneous Columbia River basalt group of Washington and Oregon.
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Ren, Qiubing, Mingchao Li, Shuai Han, Ye Zhang, Qi Zhang, and Jonathan Shi. "Basalt Tectonic Discrimination Using Combined Machine Learning Approach." Minerals 9, no. 6 (2019): 376. http://dx.doi.org/10.3390/min9060376.
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Geochemical discrimination of basaltic magmatism from different tectonic settings remains an essential part of recognizing the magma generation process within the Earth’s mantle. Discriminating among mid-ocean ridge basalt (MORB), ocean island basalt (OIB) and island arc basalt (IAB) is that matters to geologists because they are the three most concerned basalts. Being a supplement to conventional discrimination diagrams, we attempt to utilize the machine learning algorithm (MLA) for basalt tectonic discrimination. A combined MLA termed swarm optimized neural fuzzy inference system (SONFIS) was presented based on neural fuzzy inference system and particle swarm optimization. Two geochemical datasets of basalts from GEOROC and PetDB served as to test the classification performance of SONFIS. Several typical discrimination diagrams and well-established MLAs were also used for performance comparisons with SONFIS. Results indicated that the classification accuracy of SONFIS for MORB, OIB and IAB in both datasets could reach over 90%, superior to other methods. It also turns out that MLAs had certain advantages in making full use of geochemical characteristics and dealing with datasets containing missing data. Therefore, MLAs provide new research tools other than discrimination diagrams for geologists, and the MLA-based technique is worth extending to tectonic discrimination of other volcanic rocks.
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Francis, P. E., P. Lyle, and J. Preston. "A tholeiitic andesite flow unit among the Causeway Basalts of North Antrim in Northern Ireland." Geological Magazine 123, no. 2 (1986): 105–12. http://dx.doi.org/10.1017/s0016756800029769.
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AbstractA tholeiitic andesite flow unit occurs in tholeiitic basalt lava in the Giant's Causeway region of North Antrim, Northern Ireland. It is the first example of an intermediate differentiate to be found among these quartz-normative basalts. Separate magma batches for the preceding and succeeding basalt formations are indicated by their Zr/P2O5 ratios, and by the differing fractionation trends shown by molecular proportion ratio plots. The tholeiitic andesite was probably extruded in a superheated condition with few crystal nuclei, and subsequent undercooling produced an unusual fasciculate/spherulitic texture in contrast to the very fine and even grain of the host basalt. A liquid–liquid interface between the flow units shows small-scale lava mixing.